Partial downloads weren't useless, though, as other commenters have said. The PKZIP tools came with PKZIPFIX.EXE, which would scan the file from the beginning

Partial downloads weren't useless, though, as other commenters have said. The PKZIP tools came with PKZIPFIX.EXE, which would scan the file from the beginning and rebuild a missing central archive. You could extract any files up to the truncated file where your download stopped.